Continued support is sought for the Core Grant for Vision Research at Harvard Medical School. The core faculty is made up of ten members of the Department of Neurobiology and six scientists from other departments at Harvard University with whom we share common interests. All of us study the visual system, which we approach at many different levels. Current research areas include: the cell biology of the cornea and lens; the physiology and pharmacology of retinal function; visual processing in the lateral geniculate nucleus (LGN), striate cortex and extrastriate cortex; synaptic physiology of the LGN; the molecular biology of circadian rhythms; and the development of the mammalian retina and central visual pathways. The Core Grant has one resource module and three service modules. The resource module consists of multiple facilities for Neural Imaging: (1) histological imaging with conventional and confocal microscopes, (2) physiological imaging with macroscopes, microscopes and a two-photon confocal, and (3) functional and anatomical MRI. The service modules include a Machine Shop with expertise in developing equipment for physiological experiments, a Laboratory Computer Module with expertise in hardware and software for data acquisition and visual stimulus generation, and an Electronics Module with expertise in electrophysiological hardware. The modules are staffed by personnel with extensive training in the appropriate fields and are supervised by established investigators. The vision community at Harvard is large and cohesive; many collaborations already existed five years ago when the Core Grant was established. The Core Grant has been a strong force in promoting further collaborations and has helped facilitate ongoing vision research at Harvard in an efficient and cost-effective manner. Within the Department of Neurobiology alone, there are four new members of the Core Grant since the last competitive renewal. With plans for continued recruitment, this community is expected to grow.